DOS ain't dead - YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions)

YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) (Announce)

posted by boeckmann, Aachen, Germany, 30.09.2025, 16:55

> BTW how important is CHS values matching to LBA values in the partition
> table? Is there some tool that automatically recalc CHS from LBA values in
> partition table? And what CHS values should be set for partitions beyond
> 8,4GB? Is there some rule of thumb or it doesn't matter in any way?

In case cylinder > 1023 there are basically three possibilities:

a) calculate a "virtual" cylinder > 1023 based on the disk geometry and write the value modulo 1024 into the MBR
b) write a marker value as CHS, typically something like 1023/254/63
c) write total garbage

Free FDISK does a) by default, but via config option may be instructed to do b).

For partitions where cyl <= 1023, the CHS / LBA values should agree. But most tools use the LBA values. This should also be safer in case the drive is transferred between different systems, as the systems might disagree about the drive geometry.

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Complete thread:

YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - RayeR, 25.09.2025, 16:25
- YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - Laaca, 25.09.2025, 21:23
  - YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - mceric, 25.09.2025, 22:27
    - YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - Rugxulo, 26.09.2025, 04:57
      - YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - mceric, 26.09.2025, 10:05
      - YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - RayeR, 26.09.2025, 15:51
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - Rugxulo, 04.10.2025, 15:12
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - RayeR, 07.10.2025, 02:48
      - YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - Khusraw, 01.10.2025, 20:03
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - mceric, 01.10.2025, 20:46
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - Khusraw, 01.10.2025, 21:06
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - Zyzzle, 01.10.2025, 22:09
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - Khusraw, 01.10.2025, 23:08
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - RayeR, 02.10.2025, 08:31
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - Khusraw, 02.10.2025, 10:25
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - Rugxulo, 03.10.2025, 09:28
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - mceric, 03.10.2025, 12:23
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - rr, 03.10.2025, 14:35
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - Khusraw, 04.10.2025, 19:58
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - Khusraw, 04.10.2025, 20:54
        re: Jack Ellis' bad attitude - Rugxulo, 05.10.2025, 00:46
        re: Jack Ellis' bad attitude - Khusraw, 05.10.2025, 01:39
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - rr, 03.10.2025, 14:37
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - Khusraw, 04.10.2025, 19:10
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - Rugxulo, 05.10.2025, 01:00
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - Khusraw, 05.10.2025, 01:06
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - rr, 05.10.2025, 10:24
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - rr, 05.10.2025, 10:24
- YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - boeckmann, 26.09.2025, 10:53
  - YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - ecm, 26.09.2025, 15:23
  - YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - bretjohn, 26.09.2025, 23:48
    - YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - boeckmann, 27.09.2025, 13:12
      - YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - bretjohn, 02.10.2025, 01:05
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - RayeR, 02.10.2025, 18:27
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - bretjohn, 09.10.2025, 22:49
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - RayeR, 09.10.2025, 23:16
    - YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - usotsuki, 03.10.2025, 19:17
- YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - RayeR, 26.09.2025, 15:55
- YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - RayeR, 30.09.2025, 16:39
  - YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - boeckmann, 30.09.2025, 16:55
    - YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - RayeR, 30.09.2025, 18:39
      - YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - ecm, 30.09.2025, 20:07
        YSDDT 0.1.2 (DOS Toolkit for Working with Disks & Partitions) - RayeR, 02.10.2025, 08:23